The present invention relates generally to connection adaptors for hoses. More particularly, the present invention relates to connecting apparatus with multiple, coordinated coupling threads that enable a fire hose to be quickly coupled to a fire hydrant or fire truck.
Means have been provided in the prior art for quick connecting fire hoses.
U.S. Pat. Nos. 6,786,516 and 7,140,645 respectively issued to Cronley on Sep. 7, 2004 and Nov. 28, 2006 show quick-connecting couplers for attaching the male end of a hose to a female end of a suitable receptacle, including a faucet or another hose. In first embodiments, the female end of the coupler is mechanically locked in sealing engagement with a male end by means of wedges and an outer retaining sleeve. In a second embodiment, hydraulic pressure provides the final seal, with the female end being a spring split-ring locked and compressed by means of an outer locking sleeve. The depicted designs use four segments that, when attached, have around 70% combined thread contact, limiting high pressure applications.
U.S. Pat. No. 2,001,244 to Ezell shows a design that is permanently fastened to a hose with a swedge type connection and connects to a hydrant using a cam not a slide with segments. This design would be permanently attached to the hose and would not be removable after assembled. This design would not be able to withstand high pressure.
Thomson U.S. Pat. No. 3,635,501 discloses segment that expands over the threads by pressing forward. For attachment, the coupler is pressed over the male threads which will distort an segment, that will then retract into place over the male threads of the element. Designs of this nature have been unable to withstand high pressure.
Other quick-connecting couplers of interest are seen in U.S. Pat. Nos. 1,761,157, 1,920,524 and 2,267,252.
Under the pressure of fire fighting, the connecting adapter hose adapters must function reliably and quickly. Threads must mate with the hydrants or other fixtures to which they are attached, and mechanical connection must withstand high pressure. It is important that thread contact be maximized, but at the same time, it is important that after use, the adaptor be easily and quickly detachable without damaging fitting threads.